JPH05225989A - Manufacture of thin type battery - Google Patents

Abstract

PURPOSE:To achieve enhancement of the productivity and stabilization of the product quality, by providing holes for an active material in a sealant sheet on a metallic current collector, and causing retention of the active material, electrolyte, etc., and then peeling off the sealant sheet. CONSTITUTION:A metallic current collector 1 is adhered onto a base paper A, and a sealant sheet 2 consisting of a polyethylene resin is adhered on the current collector 1. Next, active material retention holes are provided in the sealant sheet 2, and a positive electrode activator 4 is coated thereon, and desiccated and crosslinked. Subsequently, a base paper B is peeled off, and a base paper C consisting of polypropylene resin and provided thereon with an exfoliation paper 5 is adhered. The resulting sheet is formed with holes 6 into which an electrolyte 7 is coated, and desiccated and crosslinked. Next, the exfoliation paper 5 of the base paper C is removed, after which a base paper D consisting of a polypropylene resin and provided thereon with an exfoliation paper 8 is adhered and holes 9 are formed therein. A negative electrode activator 10 is transferred and the exfoliation paper 8 is removed. Subsequently, a metallic current collector 11 is disposed and then thermal compression bonding is effected under vacuumized condition to seal the sealant 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a thin battery used in fields such as electronic equipment and electric vehicles.

[0002]

2. Description of the Related Art Conventionally, in the manufacture of a thin battery of this type, in a battery structure as shown in FIG. 4, an active material is applied on the surface of a current collector with a frame, and then the active material is surrounded. A thin battery was manufactured by disposing a sealing agent and stacking the respective current collectors thus manufactured.

[0003]

With such a conventional manufacturing method, mass production is difficult and quality (coating thickness, coating area / area, etc.) varies. The present invention has been made in view of the above problems, and an object of the present invention is to provide a manufacturing method that improves battery manufacturing capacity and stabilizes quality.

[0004]

In order to achieve the above object, the present invention provides a first step of providing a sheet layer made of a sealing agent on the surface of a metal current collector, which is a step for coating the sealing agent sheet layer. -A second step of forming a hole for an active material by fucating or the like, a third step of holding the active material, the electrolyte or the like in the hole, a fourth step of removing the halfcutted sealing agent sheet, and the like,
The metallic current collector is formed of a foil or a vapor deposition film, has a thickness of 0.001 mm to 0.05 mm, and has a backing sheet attached, and the backing sheet is attached to one side of the sealing agent sheet. That the active material, the electrolyte, etc. are held in the holes of the sealing agent sheet, and the thickness of the active material, electrolyte, etc. after drying is substantially the same as the thickness of the sealing agent. is there.

[0005]

In the present invention, by providing a sheet layer composed of the mount A and the sealing agent on the surface of the metal current collector made of the foil or the vapor-deposited film, the surface of the metal current collector can be prevented from being contaminated and the performance of the battery Improve. By attaching the backing sheet B to the sealing agent sheet, the surface of the sealing agent is prevented from being soiled when the active material is held (by coating or the like), and the sealing performance of the battery is improved. The active material region is made constant by forming holes for the active material from the top of the mount B by means of half cut in the sealing agent sheet layer. The thickness of the mount sheet B of the sealing agent sheet also has the effect of making the applied active material, the electrolyte, etc., have a thickness substantially equivalent to the contracted thickness due to drying, and facilitates the application in the next step (eg, the electrolyte application step). Further, the metallic current collector is a foil or a vapor-deposited film having a thickness of 0.001 mm to 0.05 mm, and by attaching the backing sheet A, it becomes easy to wind it by a roll or the like, and the flexibility is improved. It can process at high speed.

[0006]

EXAMPLES Details of the present invention will be described below with reference to examples. As shown in FIG. 1, a mount A made of polypropylene resin with a width of about 400 mm (thickness is about 0.1 m
m) on top of stainless steel foil (width: 300 mm, thickness: 0.0
2 mm) of the metal current collector 1 is adhered, and the release paper B made of polyethylene resin is attached to the surface of the metal current collector 1 on the upper surface.
2 sheets (width: about 300 mm, thickness: about 0.05 mm) of a sealing agent made of polypropylene resin to which (width: about 300 mm, thickness: about 0.01 mm) were adhered. The above corresponds to the first step. Next, the sealing agent 2 was half cut to form the holes 3 for holding the active material. The above is the second
It corresponds to a process. Further, a positive electrode active material 4 having a thickness of about 0.06 mm was applied to the hole 3 with a doctor coater. It was then dried at about 100 ° C to about 250 ° C. At this time, the thickness of the positive electrode active material 4 contracted by about 20% to about 0.05 mm. Then, it was cross-linked by electron beam irradiation. Next, the mount B is peeled off, and then the mount C made of polypropylene resin having the release paper 5 on the upper surface (width: about 300 mm, thickness: about 0.
02 mm) was glued from above. Further, a hole 6 larger than the hole 3 was formed in the mount C by half cut. Subsequently, the electrolyte 7 was applied to the holes 6 with a doctor coater. After drying, it was crosslinked by electron beam irradiation. Next, the release paper 5 of the mount C was removed, and then the mount D (width: about 300 mm, thickness: about 0.02 mm) made of polypropylene resin provided with the release paper 8 was adhered again. Next, a hole 9 which is almost the same as the hole 3 is formed in the mount D again by half cut. Further, the half-cut negative electrode active material 10 was transferred to the hole 9 in another step. Then, after removing the release paper 8, the metal current collector 11 (the backing sheet A is adhered to the outer surface) manufactured in the same manner as in the first step is arranged, and thermocompression-bonded under reduced pressure to obtain the sealing agent 2. ,
The inside of the battery was vacuum-sealed with a mount C and a mount D (a sealing agent may be adhered to the inner surface of the metal current collector 11 in advance). Next, the outer periphery of the battery (leaving the outer periphery of the mount A slightly) was half-cut.

FIG. 2 is a perspective view of the thin battery 12 thus obtained, and FIG. 3 is an enlarged cross-sectional view taken along the line II of FIG. At this time, the terminals 13 and 13 'are arranged vertically. In this state, the mount A is adhered to one surface of the terminals 13 and 13 'to prevent an electrical short circuit.

In the conventional manufacturing process, the maximum number of batteries produced is 30.
While the cell / minute was 100 cells / minute in the present invention.
This corresponds to mass production. In addition, Table 1 shows the variation in battery capacity and the defective rate during manufacturing.

[0009]

Further, Table 2 shows the airtight defective rate and the voltage drop value of the metal current collector due to bending during roll feeding when sequentially processing the current collector when the thickness of the metal current collector is changed. It was

[0011]

As can be seen from Table 2, the thickness of the metal current collector is preferably in the range of about 0.001 mm to 0.05 mm from the viewpoint of productivity and battery performance.

[0013]

As described above, according to the present invention, the productivity (mass production) of the battery is improved and the battery performance is improved. Therefore, the mass productivity and the reliability are higher and the industrial value is extremely higher than the conventional one.

[Brief description of drawings]

FIG. 1 is a perspective view showing a process state progress of each step in manufacturing a thin battery of the present invention.

FIG. 2 is a perspective view of the thin battery of the present invention when it is completed.

FIG. 3 is an enlarged cross-sectional view of a II section in FIG.

FIG. 4 is a perspective view of a manufacturing procedure of a conventional thin battery.

[Explanation of symbols]

 1, 11 Metal Current Collector 2 Sealant 3, 6, 9 Hole 4 Positive Electrode Active Material 5, 8 Release Paper 7 Electrolyte 10 Negative Electrode Active Material 12 Thin Battery 13 Terminal 13 'Terminal

Claims (4)

[Claims] 1. A method for manufacturing a thin battery comprising a power generating element in which a positive electrode active material, an electrolyte layer and a negative electrode active material are layered, and a sheet layer made of a sealing agent is provided on the surface of a metal current collector. 1 step, 2nd step of forming holes for active material in the sealing agent sheet layer by half cut, etc., 3rd step of holding active material, electrolyte etc. in the holes, said half cut sealing agent sheet -A method of manufacturing a thin battery, comprising a fourth step of removing the battery. 2. The metallic current collector is formed of a foil or a vapor deposition film and has a thickness of 0.001 mm to 0.05 mm,
The method for manufacturing a thin battery according to claim 1, wherein a mount made of a sealing agent, a peeling resin, or paper is attached. 3. The method of manufacturing a thin battery according to claim 1, wherein a mount made of resin or paper for peeling is attached to one surface of the sealing agent sheet. 4. The active material and the electrolyte are held in the holes of the sealing agent sheet, and the thickness of the active material and the electrolyte after drying is made substantially equal to the thickness of the sealing agent. Alternatively, the method for manufacturing the thin battery according to the above item 3.